Title

The Kubernetes API server must have the insecure bind address not set. (Cat I impact)

Discussion

By default, the API server will listen on two ports and addresses. One address is the secure address and the other address is called the "insecure bind" address and is set by default to localhost. Any requests to this address bypass authentication and authorization checks. If this insecure bind address is set to localhost, anyone who gains access to the host on which the master is running can bypass all authorization and authentication mechanisms put in place and have full control over the entire cluster. Close or set the insecure bind address by setting the API server's --insecure-bind-address flag to an IP or leave it unset and ensure that the --insecure-bind-port is not set.

Check Content

If running rke2 Kubernetes version > 1.20, this requirement is not applicable (NA). Ensure insecure-bind-address is set correctly. Run the command: ps -ef | grep kube-apiserver If the setting insecure-bind-address is found and set to "localhost", this is a finding.

Fix Text

If running rke2 Kubernetes version > 1.20, this requirement is NA. Upgrade to a supported version of RKE2 Kubernetes.

Additional Identifiers

Rule ID: SV-254560r954708_rule

Vulnerability ID: V-254560

Group Title: SRG-APP-000033-CTR-000095

Expert Comments

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